Need Large display DMM for biasing amps

Hi tube aficionados

The need to bias some amps accurately with an outboard meter, has my attention expressly as of late. My particular needs are for a meter whose display is either really big, or one that can be displayed onto another screen Ie., LCD, CRT, or PC.

Anyone have any knowledge of a DMM which has a large high contrasting display? Or One that can be used with a monitor or PC?

Characters over one inch for sure is definitely needed . 1.5 inches or larger would probably work fine. Accuracy of the meter function of course, is important too.

Any suggestions in this regard would be a big, big, help.

Thanks very much.
The Fluke meters are considered some of the best and some can be connected to a PC. They can be expensive though.
Blindjim, Radio Shack used to make an excellent talking digital multimeter which I still own. The following individuals may have information about magnifying or talking DMMs:
Marc Riccobono, Ann Taylor and Stephen Booth at NFB Baltimore: 410-659-9314.
Ken Gould of Audio Nexus: (908) 277-0333.
Chris Chamberlyn (audiogoner Frontier1) of Frontier Computing: 416-489-6690.
Bradley Hodges and Jay Leventhal of AFB: 212-502-7600.
Marc Mulcahy of Levelstar: 800-315-2305 (x.701).
Larry Skutchyn ()pron Scootkhan) of APH: 502-895-2405.
Steve Barkeley of AROGA: 604.431.7997.
Marvyn Sandler at Independent Living Aids: 800-537-2118.
Thanks... I'm seeing several online at various sites but I'm wondering if the info being sent to the PC isn't past tense info... I would need real time, "right now" feedback viewable as it changes on the screen...

I did glean the triplet, and Fluke cust service #'s late last night so I'll be in touch with them Monday.

Whoa. Thanks very much.
The only talking meter I've seen anyone talking about online, was one made by Omega, and is now out of production. In fact there was a blog by one buyer who had issues upon receipt of his and he let it slip he was visually impaired (not knowing that would matter), and Omega would not repair the unit for him and insisted on him ONLY returning the meter to them.... as Omega said the "talking meter" was not intended for use by blind, or visually impaired people, as such use posed a hazzard to the user... and apparently, Omega wanted no part of it at all.

I will start calling those numbers Monday and see what's up with what. thanks again.
In microbiology labs, "Quebec Colony Counters TM" used to be used to quantify microbial colonies on agar plates. These simply provided a backlit grid over which a petridish was placed. Above the dish a magnifying lens was suspended. I'm guessing, but magnification is on the order of 10X??? (don't have access to one at the momment. Would some sort of mounted magnifying lens help with visualization of read out from a conventional meter?

Sounds good BlindJim, let me know how the quest goes. . . there are many ways to skin this particular cat. Ghosthouse, yes there are dedicated magnifying lenses and mono/binoculars for visually impaired people. Problem with magnifying lenses is that they tend to distort the image. A better solution may be to place the display of a regular DMM under one of the many electronic magnifyiers for VIPs available from such companies as Humanware, Freedom Scientific, Optalek, Guerrilla Technologies and so forth. These things used to be Huge, but now they are sometimes smaller than a paperback book and are quite flexible in their applicability.
yes. Either 1.5 inch characters are the now need... or some other gizmo is necessary.... and I may have one that I had not thought of lately as it sees such little use..

Guidocorona is right. As magnification increases the field of view diminishes... and distorts some as well. usually it will remain legible or at least intelligible... enough. Under severe mag, as the field size drops you can end up getting down to just one character, or even a portion of it. So be it.

That is truly not too much the issue... the issue is hands free determination of the integers being displayed... as one hand is busy holding the bias switch, and the other turning the screwdriver.

I recently acquired an "AMIGO" portable blower-upper. Rechargeable battery powered. Super huh? Nope.

No good. Why?

The back light of the meter itself. It blinds the CCD chip inside the AMIGO and covers the area with a big spot which hides the numbers… but it’s a fine device for non back lit things… and costs about the price of a nice sub, or good DAC. >$1500.

The current RAT SHAK meter numbers are about 0.5 or 0.6 in tall.... and if the light weren't on when the meter is on, I'd have a shot then.

But hey, it's nothing but a thing. It'll all work out. It always does. I just gotta do some serious leg work and seek another path. Nuttin' to it.

... and a large read out I think is the ticket. I got enough beeping, booping, buzzing, and talking stuff around here already.
Just for closure... and the benefit of those whose eyeballs have seen better days.

I pursued all of the listings posted previously in this thread... many to no avail. Although I am grateful for each and every one of them BTW.

By doing some surfing and countless Google searches, as well as receiving the input of some other members offline, (thanks Tim & Chris), i found some nifty gizmos for digitally measuring electrical values, and some other values pertinent to audio.

For a simple inexpensive unit, Triplett has a large display DMM which has 1+ inches tall characters, some sites say 1.5, but the maker says 1.15 inches. Period. Model 9005 & 9015. Neither are Auto ranging, nor will they interface with a PC.

Fluke also has a few models which allow for disabling the back lighting function which will be of immense value if a CCTV is used to read the numbers. The 80 series models namely the 87v at $350 list.

Fluke also has an RS 232 (USB) INTERFACE ON SOME MODELS. One 'All in one' package item is the model # 189 FVF2. it comes complete with all the needed cables, and software necessary to get the info from the portable DMM into the PC and either log it all for reference, or see it in real time! The price tag is $500. it also does far, far more than what you might expect from a DMM. The Fluke also has the best accuracy of those listed here.

Extech MM560 is yet another handheld which does nearly all the Fluke 189 FVF2 does BUT comes in at a lesser tag, of $319. The Txtech also provides real time results via the PC.

Still available are LED read out meters which do consume more energy than the LCD types, yet have higher contrasting displays. many of these are bench models, though some do have self contained power sups for portability. TTi an English co. offers a model 1604 bench type with red LED display.

There are far more units that will aid those with limited visual skills or whose eyes aren't what they used to be. it will depend upon your specific needs which choice you may make.

My persoanl solution came via a Jordy II portable head set with docking station. I used it briefly as a portable unit. in it's current state of use as a standard CCTV, it serves the purpose... and one last 'trick' if using a CCTV with back lit DMMs, turning off the light (if possible) on the CCTV being used may help defeat the glare the back lit meter produces. Some other ambient light may well suffice.

Thanks for all the help folks.
Thank you Blindjim for all the excellent info. As I have graduated to pure non visual UI two and a half decades ago, I am intrigued by the Fluke with USB capability. I would interface with the ICON talking PDA, which is all based on LINUX and Python. If you were interested in this little beauty, you will find info at:

One last note for those like myself in need of a large digital readout DMM.

This one has a 2 inch LCD display with many automatic features. it is geared for the pro auto tech but serves the functions of audio gear testing quite well too.

Do check with the maker for it's accuracy tolerances if that is a concern though I'd think it fine enough for even the more serious hobbyist. For under $100 it's the most fully featured, DMM with the largest display I've found yet.

It could save one some money on auto repairs too if you're into that and can pull yourself away from the sweet spot long enough to go work on the grease spot.
For closure...

I just received the ESI 590 DMM w/2 in. display. it came with everything one could want, amprobe that can measure up to 20A, alligator terminated leads, reg. test leads, temp probe, carry strap, carrying case, and battery.

I got it online at:

for just over $100.00, this site isn't big on sending an invoice quickly, yet the unit arrived on a timely basis, and the price was good.

The enclosed and installed battery was dead. replacing it got things going in a positive direction. ESI is accessible by phone or email too, that's a plus as well.

Contrast is as important for me than is simply a large display, apparently. All things considered however, this unit is going to work out well I think.

It's accuracy exceeds that of some others yet falls a bit short of the better names like Fluke for instance.... but at 0.5% (.005) on DC/AC voltages, I think I can live with that!

Add to that the fact one can now check their fuel injectors 'pulse modulation width' and how could anyone ask for more? ..and it's covered in a red rubber finish w/stand.

BTW I've no affiliation with either the maker or the seller of this product.
Could you get a unit you can easily afford and use one of those swing away magnifying units, the large ones that are like 8 inches in diameter would work right?

Thanks. good thoughts.

that comes down to ergonomics I think. it's fairly cumbersome to incorporate an additional magnifyer lens. For that part I'd likely just use the Jordy II CCTV & my office TV.

Contrast is more the issue. With this ESI-590 DMM I think with a small light afixed somewhere, I'll be able to discard the CCTV path altogether.... for a while, anyways. The ESI DMM backlighting feature can be toggled on & off and with the proper lighting and angle I can actually see the display OK. Mostly. white numbers on a black background would be better by far.... but things are what they are, huh? Deal with 'em and move on. add to that the fact the ESI folks sent me the manual in .pdf, and I'm pretty well set.

In fact the amps need far less attention than I give them... once set and re-checked they hold bias pretty well. Any drift at all comes from extensive or energetic playing, and then it isn't very much... and newer output tubes will likely remedy that, as these are probably getting on.

Thanks again for the thoughtfulness.